DE 23 05 780 describes a multi-stage planetary gear, in which the planet wheels are held on the pins of the planet carriers and the individual stages are held against one another by a slide ring system.
DE 198 53 459 describes a multi-stage planetary gear, in which a single internal gear is provided with a single inner toothing, with which all planet carriers mate.
DE 33 30 337 describes a power turning device, which has a housing part, in which a single-stage or multi-stage main gear is located. At the input side of the housing part, a housing part is fastened in a detachable manner, which contains an additional gear stage.
U.S. Pat. No. 4,437,530 describes an axle drive device for driving vehicle wheel devices, which includes a differential mechanism for driving axle shafts.